Floyd Mayweather, Jr. is walking into a chamber. It looks like a high-tech shower, or a teleportation device from The Jetsons. Liquid nitrogen vapors rise around his face as a digital counter shows the temperature dropping: -110° F, -120°, -121°.

The footage is from a 2015 promotional video for the Las Vegas spa SubZero Recovery. (Mayweather is an investment partner.) SubZero specializes in cryotherapy, a treatment that uses extremely low temperatures to ostensibly help reduce pain and inflammation and aid in overall recovery.

Advertisement - Continue Reading Below

David Levi, the owner of SubZero Recovery, says the boxer became a fan of the therapy after receiving more localized treatments on his hands, elbows, and back. “Little aches and pains that Floyd had in his elbows and hands wouldn’t bother him for two to three days [after the treatments],” Levi told Men's Health.

“The cryotherapy session we did is an element of my training camp to help me recover between one training session and another in the same day,” Bivol, 27, told Men’s Health via his manager and translator. “It helped me a lot. I’ve only tried it a couple of times, but I plan to use it when I feel that my body is a little overwhelmed.”

With so many athletes singing the praises of cryotherapy, we at Men's Health wanted to know: does it actually work? And if so, is it safe? We spoke to some industry leaders to get some answers.

Basically, there are two different types of whole-body cryotherapy: electric cryotherapy, which uses fresh, oxygenated air to uniformly cool the whole body; and liquid nitrogen cryotherapy, which exposes users to liquid nitrogen vapors. During treatment, temperatures plunge to below-freezing levels of anywhere between -166° Fahrenheit (the average temperature for an electric cryotherapy chamber) and -256°F (the coldest temperature for liquid nitrogen cryotherapy).

While electric cryotherapy involves walking into what is essentially a refrigerated sauna, liquid nitrogen cryotherapy treatment requires the user immersing himself into a narrow chamber, their head and upper chest area sticking out of the chamber for ventilation. The vapors then rise around the body, conjuring images of former WWE Superstar The Undertaker’s ring entrance. An individual treatment usually takes about two to three minutes, with sessions usually costing somewhere between $40 and $100 each. Your body temperature drops about 30 – 45 degrees following treatment, at which point you’ll be encouraged to do about five minutes of moderate cardio to get back to normal.

“It’s a thermogenic treatment. You expose the skin to a really cold temperature that activates the central nervous system, which is designed to be regulated by the skin,” claims Kevin Kramer, the co-owner and chief operating officer of U.S. Cryotherapy, which has over 20 locations nationwide. “So extreme temperatures send this kind of shock signal to the brain."

“We found very little evidence about [cryotherapy's] safety or effectiveness."

“Cryotherapy and cold-water immersion are two forms of cold exposure,” Patrick said on the podcast. “Cryotherapy — just two minutes at -180°F — can increase norepinephrine two-fold."

Additionally, in a May 2006 randomized controlled trial published by the National Center for Biotechnology Information, patients suffering from rheumatoid arthritis seemed to experience a decrease in pain and inflammation after two to three cryotherapy treatments at -166°F daily for one week in addition to conventional physiotherapy.

Advertisement - Continue Reading Below

Advertisement - Continue Reading Below

But that controlled trial had a relatively small sample size of 60 patients, which makes it far from conclusive. Further, other studies have produced contradictory results, with some indicating that cryotherapy does not yield any positive benefits at all.

Inside a U.S. Cryotherapy chamber.

The Food and Drug Administration (FDA) also isn't sold on cryotherapy's benefits. In a July 2016 report, the FDA referred to whole-body cryotherapy as “a so-called ‘treatment’” that “lacks evidence," urging those interested to consult their doctors before stepping into a deep-freeze chamber.

“We found very little evidence about its safety or effectiveness in treating the conditions for which it is being promoted," Aron Yustein, M.D., a medical officer in the FDA’s Center for Devices and Radiological Health, said in the report, adding that no whole-body cryotherapy devices have been approved by the agency for therapeutic use.

Worse, in 2015, the Associated Press reported that Chelsea Ake-Salvacion, 24, a former employee of RejuvenIce Cryotherapy, died following an unsupervised cryotherapy treatment. “When they found her, she was frozen rock-solid,” Ake-Salvacion's uncletold the Associated Press. (An autopsy later found that Ake-Salvacion died not of hypothermia but of asphyxiation, triggered by oxygen levels plummeting to roughly five percent.

Getty Images

Advertisement - Continue Reading Below

Advertisement - Continue Reading Below

In response to claims that liquid nitrogen cryotherapy is unsafe, Levi says that the risk of injuring users is slim, provided users adhere to protocol while inside the chamber. (Most treatments are administered by a technician waiting outside, while Ake-Salvacion was unsupervised.) Levi added that since SubZero Recovery opened in April 2015, there have not been any reports of injury.

"If someone is rotating in the machine the entire two to three minutes, there’s absolutely no way that they could get burned," he says. "We’ve never seen anyone get burned in our place.” (Liquid nitrogen at sub-zero temperatures is also used in cryosurgery to burn off skin tags, warts, or other types of abnormal tissue, but that's always under medical supervision.)

Yet despite negative media coverage following Ake-Salvacion's death, the trend has continued to gain steam. While the Los Angeles Lakers, Minnesota Vikings and Detroit Pistons, to name a few, have installed or are planning to install electric air cryotherapy chambers at their facilities, Kramer says that plenty of average Joes are also becoming regulars at cryotherapy centers.

“Most of our clients right now are people with chronic pain or post-surgery. We have youth athletes … [who] become loyal users,” Kramer says. (Unlike SubZero Recovery, U.S. Cryotherapy only uses electric chambers cooled with oxygenated air. It does not offer liquid nitrogen cryotherapy treatments.)

Kramer also adds the caveat that cryotherapy is not a one-and-done kind of treatment. The effects, he says, are optimized when users do it consistently.

“It’s a lifestyle thing,” he adds. “You don’t go to the gym once, walk away and say, ‘Oh, great, I’m done.’ If you incorporate cryotherapy [regularly], the benefits are there.”

A Part of Hearst Digital Media
Men's Health participates in various affiliate marketing programs, which means we may get paid commissions on editorially chosen products purchased through our links to retailer sites.